1. Field of the Invention
The present invention relates to power equipment, including but not limited to mowers, tillers, snow blowers, and tractors, and more particularly, to a blade brake and clutch for power equipment.
2. Discussion of Related Art
Conventional power equipment can include a clutch that selectively engages the mower blades with the engine output member. A brake that retards the rotation of the mower blades when the mower blades are disengaged from the engine output member might also be included. The combination of these two coupling devices permits the operator to control the movement of the mower blades independently of the engine output member.
Typically, the components utilized in the clutch are separate and distinct from those employed by the brake. This arrangement creates a large number of parts for assembly as well as for replacement under routine maintenance. This routine maintenance is further hampered by the need to disassemble a relatively large number of parts to replace the worn or broken part(s).
Dimensional constraints are another drawback of conventional blade brake and clutch designs. A large surface area is desirable for both the brake and the clutch. However, packaging space often constricts these areas below their optimum values.
Accordingly, the present invention is directed to a friction coupling that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a maximum frictional surface area with a minimum radial dimension for the friction member. This arrangement minimizes the number of parts needed for assembly and maintenance.
Another object of the present invention is to provide a compact assembly that is adequately shielded.
Another object of the present invention is to provide an uncluttered appearance.
Another object of the invention is to minimize the number springs needed to bias the brake and the clutch.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, a friction coupling includes: a friction member including a brake surface and a clutch surface in a different plane from the brake surface; a spring abutting the friction member; a brake member proximate to the brake surface; the brake member mounted relative to the friction member to permit relative rotation; and a brake actuator connected to the brake member.
In another aspect, a drive assembly includes: a driving member; a driven member; a friction member, the friction member including a brake surface and a clutch surface in a different plane from the brake surface; means for rotationally fixing the friction member to one of the drive member and the driven member and for permitting axial displacement of the friction member relative to the driving member and the driven member; a brake member proximate to the brake surface; the brake member mounted relative to the friction member to permit relative rotation; and means for moving the brake member between a first position in which the brake member is engaged with the brake surface and the clutch surface is disengaged with the other one of the driving member and the driven member and a second position in which the brake member is disengaged with the brake surface and the clutch surface is engaged with the other one of the driving member and the driven member; and means for biasing the moving means into the first position.
In a further aspect, a blade brake and clutch assembly for a lawnmower includes: an engine output member; a blade holder; a coupling having a first position and a second position, the coupling including: a friction member including a brake surface and a clutch surface separate from the brake surface, the friction member being connected to one of the engine output member and the blade holder; a first spring located between the friction member and the one of the engine output member and the blade holder; a brake member proximate to the brake surface; the brake member mounted relative to the friction member to permit relative rotation; and a brake actuator connected to the brake member; the clutch surface being disengaged from the other one of the engine output member and the blade holder and the brake member being engaged with the brake surface when the coupling is in the first position and the clutch surface is engaged with the other one of the engine output member and the blade holder and the brake member is disengaged from the brake surface when the coupling is in the second position.
In a further aspect, a drive assembly includes: a driving member; a driven member; a friction member, the friction member including a brake surface and a clutch surface in a different plane from the brake surface; a coupling rotationally fixing the friction member to one of the drive member and the driven member and permitting axial displacement of the friction member relative to the driving member and the driven member; a brake member proximate to the brake surface; the brake member mounted relative to the friction member to permit relative rotation; and a brake actuator connected to the brake member to move the brake member between a first position in which the brake member is engaged with the brake surface and the clutch surface is disengaged with the other one of the driving member and the driven member and a second position in which the brake member is disengaged with the brake surface and the clutch surface is engaged with the other one of the driving member and the driven member; and a first spring biasing the brake member into the first position.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.